Corpora annotated at fine-grained levels (opinion- or aspect-level) require more effort from annotators, but are able to capture information which is not present at document- or sentence-level, such as nested opinions or differing polarities of different aspects of a single entity. In English, the MPQA corpus [1]} has been widely used in fine-grained opinion research. More recently, a number of SemEval tasks have concentrated on aspect-level sentiment analysis [2]}, [3]}, [4]}.
